1. Field of the Invention
The present invention relates to a technology that makes it possible to reduce the power consumption of an external accessory attached to an electronic apparatus.
2. Description of Related Art
A portable electronic apparatus normally assumes a structure that allows external accessories, via which various functions are provided, to be attached thereto. Such external accessories include those that operate on power supplied from a battery in the electronic apparatus. The power supply to this type of external accessory is turned off immediately when the power to the electronic apparatus is turned off.
There are external accessories that require initialization processing and the results of the initialization processing may be retained over a predetermined length of time after the power to the accessory has been turned off. Such an external accessory may be utilized by intermittently executing the external accessory initialization processing while power at the electronic apparatus is in the OFF state so as to assure the following advantages. First, since the initialization processing does not need to be executed when the power to the external accessory is turned on, the length of wait time to elapse before the completion of the initialization processing is reduced. Second, unnecessary power consumption at the external accessory is minimized. Japanese Laid Open Patent Publication No. 2007-158886, for instance, discloses a technology for determining the operational intervals for a GPS module connected with an imaging apparatus based upon the frequency with which the imaging apparatus is used.